目標：以往勞農保的生育是採現金給付，婦產科診所在醫療可近性高以及收費低的優勢下，業績興隆。全民健康保險開辦後，生育改為實物給付，服務價格由保險人統一訂定，診所的優勢不再。本研究擬檢驗在競爭的壓力下，婦產科診所會對產婦出生時間的訴求有比醫院更為正面回應的假說。方法：以民國87年的出生證明資料為基礎，利用邏輯迴歸模式，在控制醫療因素後，觀察醫院與診所在工作時間、週末與週間、以及日子吉凶分類下的剖腹產率差異。結果：醫院星期六、日的剖腹產率皆較週間為低；診所星期六的效果相反。吉日吉時白班的剖腹產率超過50%，凶日夜班的剖腹產率低於20%；晚班及夜班的剖腹產率以診所為高。結論：為了維持競爭力，婦產科診所比醫院更願意在非正常工時內施行剖腹產。夜班凶日時段的剖腹產率接近WHO建議的15%水準，應是努力的目標。

　　　　　Objectives: Since the maternity benefits in the Labor Insurance and Farmers?Health Insurance schemes were cash benefits, obstetric & gynecological clinics attracted more clients due to their easy accessibility and lower charges. However, the implementation of the National Health Insurance altered their comparative advantages by changing the cash benefits to in-kind services. We believe that clinics have reacted more positively than hospitals toward the maternal requests regarding the timing of birth. Methods: In this study we used data from birth certificates issued in 1998 to examine the difference in cesarean section rates between hospitals and clinics during office and non-office hours, weekdays and weekends, as well as auspicious and inauspicious days. Results: After controlling for all the confounding factors, the regression results indicate that the cesarean section rates are lower on Saturdays and Sundays for hospitals; however, the rates are higher on Saturdays for clinics. During regular office hours of auspicious days, the cesarean section rates are above 50 percent, but the rates are below 20 percent for the night shift of inauspicious days. During the evening and night shifts, the rates are higher in clinics. Conclusions: To stay competitive, clinics are more likely to perform cesarean sections during their non-office hours. Cesarean section rates for the night shift of inauspicious days are close to the WHO recommended level (15%), which should be our ultimate goal.